The present invention relates to electronic identification devices, and in particular to an inexpensive, high speed, identifier apparatus that when placed near a passive or active transponder is able to receive and decode an ID signal transmitted by the transponder, as well as provide operating power to the transponder, if it is a passive transponder.
Identification (ID) devices and systems are known in the art. See, e.g., U.S. Pat. Nos. 3,859,624; 3,878,528; 4,095,214; 4,129,855; 4,354,099; 4,475,481; 4,549,264; and 4,739,328. Typically, such devices and systems are used for (1) access control, (2) animal feeding and animal health, (3) inventory control, (4) process control, and/or (5) theft/security applications.
A representative identification system includes: (1) a transponder that transmits a unique identification (ID) signal; and (2) a receiver, or "reader" that receives and decodes ("reads") the ID signal. The transponders are typically small, inexpensive, devices that perform the dedicated function of generating and transmitting their unique ID signal in response to being interrogated by a "reader". The transponders are placed on, or carried by, objects, animals, or persons that are to be identified. The "readers" are placed near a location where an identification is to be made. Hence, when an object, animal, or person carrying a transponder comes near a "reader", the reader is able to trigger the generation of the ID signal, receive the ID signal, and decode the ID signal so as to identify the particular object, animal, or person to whom the transponder has been attached. In response to making such a valid identification, the "reader" may then generate appropriate control signals that carry out a desired function, e.g., the unlocking of a door, the dispensing of a prescribed amount of food, the turning on of a video camera or audio recorder, the time logging of the ID signal, the enabling of a piece of machinery, and the like.
Some identification systems may utilize a transmitter to generate the ID signal, as opposed to a transponder. In such instances, the transmitter periodically generates and transmits the ID signal, e.g., once every 10 seconds, regardless of whether the transmitter is near a "reader". However, the ID signal is of limited range, so the ID signal is only received by the "reader" when the transmitter is in close proximity thereto.
The present invention relates primarily to the "reader" device, hereafter also referred to as an "identifier" device or apparatus. Equipment presently used to perform the function of the identifier apparatus in an electronic identification system is generally one of two types. A first type is a "portable" identifier used to read transponders on animals, packages, or people. Such portable identifier typically is about the size of a clothing iron, and may weigh several pounds. Some older portable readers or identifiers are much larger, and are so bulky that they must be placed on a strap and hung over the shoulder of a user. But even when only the size of a clothing iron, the carrying and positioning of such identifier apparatus can become tiring and burdensome. Thus, there is a need in the art for a smaller, more compact, and light weight identifier device.
The second type of identifier device used in the art is a "stationary" identifier, typically permanently housed in a box mounted on a wall or door, and used to read a transponder-type security badge. In most cases, in order to keep the size of the box small and unobtrusive, an antenna and a minimum amount of circuitry is housed in the box, while the remaining circuitry is housed in another (usually hidden) box mounted in the ceiling or elsewhere. The separating of the circuitry between two or more boxes in this manner results in increased expense, maintenance and circuit complexity. What is thus needed is an identifier device that can perform all the identifying functions needed by the security system using inexpensive circuitry that may be housed in a single, small, unobtrusive housing.